①If a child has brown hair and blue eyes, one or both of the child’s parents probably has brown hair and blue eyes. Why? Genes (基因). Scientists know that the way people look is passed down from parent to child by information in genes. But how about other things? If a parent is shy, then would the child also be shy? If a parent is smart, then will the child also be smart? Scientists want to know how much genes and ways of raising can affect (影响) a person.

②One way scientists have studied this question is by studying identical twins who were separated (分开) at birth. Identical twins are twins that look the same on the outside. They also have the same genes on the inside. This is how scientists study their nature. Many years ago, when twins were given away to other families at birth, they didn’t always go to the same family. So, they were separated and raised in different ways. This was of great interest to scientists. Even if the twins had the same genes and looked the same, did they turn out the same as adults? Here are what the scientists have found.

③For some things, such as looks or diseases, the twins turned out the same. Even if one twin drank lots of milk and the other did not, they were of similar heights as adults. Even if one twin exercised and ate healthy food and the other did not, they could get the same disease as adults. Scientists found that how each twin was raised could not change much.

④However, in the case of personality (个性), the answer is not so clear. Some separated twins had completely different personalities and lives as adults. Other separated twins were almost exactly the same. They dressed the same, talked the same, and even had the same jobs—even though they had never met!

⑤In the end, there seems to be no simple answer. As a whole, it seems people become who and what we are because of both genes and how we are raised.

【小题1】How does the writer lead in the topic?

A．By telling stories.	B．By asking questions.
C．By comparing facts.	D．By listing numbers.

【小题2】Whom were the scientists interested in studying according to Paragraph 2?

A．The identical twins who grew up together after they were born.

B．The identical twins who had different genes and looks.

C．The identical twins who looked different but had the same genes.

D．The identical twins who grew up in different families from birth.

【小题3】What do Paragraph 3&4mainly talk about?

A．The importance of the study.	B．The ways of the study.
C．The results of the study.	D．The rules of the study.

【小题4】Which of the following will the writer most probably agree?

A．Genes and how we are raised make us who we are.

B．We become who we are mostly because of our genes.

C．The people we become depend on how we were raised.

D．Genes are the main reason for personality development.